Few cities witness the arrival of a 3,000-tonne bridge deck by river. But in Nantes, residents watched as a steel span 150 metres long and eight storeys high was floated into position with remarkable precision, using the tide as a tool.

The installation of the new span for the Anne-de-Bretagne Bridge was not just another bridge lift. In several respects, it represented one of Europe’s most unusual urban marine engineering operations of recent years, according to civil engineers Schlaich Bergermann Partner (SBP), the brains behind the operation.